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Researchers in Spain found in a recent study that people who rise later in the day tend to possess qualities associated with higher general intelligence in addition to greater mean incomes and more comfortable lives. CDC.gov

A new study suggests the early riser has only more time for mediocrity.

Researchers at the University of Madrid followed nearly 1,000 teenagers and found that night owls bested "morning larks" in qualities linked to general intelligence, such as inductive reasoning, conceptual and analytical thinking.

"What hath night to do with sleep?" asked John Milton, the 17th century English poet who worked as a civil servant, among a class of people generally obliged to rise early in the morning.

Indeed, while many early risers outperform night owls in school, researchers said the late risers surpass their counterparts later in the workforce. Differences in preset circadian rhythms might explain the 8 percent advantage enjoyed by early risers in school, researchers said. Though outliers such as former U.S. President George W. Bush, Thomas Edison and Ernest Hemingway achieved phenomenal success as early risers, such people on average tend to make good civil servants and accountants, whereas later risers tend to demonstrate traits linked to greater occupational success and higher incomes.

A previous study conducted by the U.S. Air Force also showed later-risers superior in "lateral thinking," even when researchers tested them in early morning. A study by the University of Southampton further found that later-risers achieved larger mean incomes in addition to all of the trappings of the good life: a more comfortable home, access to a car, and less manual labor.

Jim Horne, a professor of psychophysiology at Loughborough University, commented on the Spanish study. "Evening types tend to be the more extrovert creative types, the poets, artists and inventors, while the morning types are the deducers, as often seen with civil servants and accountants."

In comparing the two types, Horne said stark differences in personality emerged. Scientists have "found that personalities tended to be different -- evening types were more social, more people-oriented," he said.

"They will probably be good at cryptic crosswords, while morning types go for the more logical ones."

The researchers in Spain identified 32 percent of the study population as night owls and one-quarter as larks, with the remaining group falling into neither category. In an attempt to explain the difference between these two groups, some scientists say night owls might experience superior intelligence given the evolutionarily novel behavior associated with activity past sunset, behaviors that tend to attract those with a more inquisitive mind.

However, a study published last year in the journal Emotion showed morning people to be happier than night owls -- their natural rhythms more in tune, perhaps, with that of modern society in general.